Diamond wholesalers and traders were dismayed to hear that even if a green diamond were certified to be Kimberley Process compliant, if the stone originated from Zimbabwe – where many green diamonds come from – the stone would still be in violation of U.S. sanctions against Zimbabwe. The Natural Color Diamond Association (NCDIA) and the Jewelers Vigilance Committee (JVC) held a seminar in New York City to answer queries about what diamantaires can do to acquire green diamonds without running afoul of U. S. law.

Zimbabwe probably accounts for 50 percent of green diamond production globally, if not more, estimated Tom Gelb, the educational director at the NCDIA. Despite many Zimbabwe mines becoming increasingly Kimberley Process compliant, existing diamond trading sanctions on the country by the U.S. mean that the diamonds cannot legally enter the country, said Cecilia Gardner, the president of JVC.

The best way a trader can be protected when dealing with green diamonds, according to Gardner, is to ask for a certificate stating whether the stone is Kimberley Process compliant and its origins. When trading polished green diamonds, traders should ask for a warranty stating that the stone was Kimberley Process compliant in its rough form and for verification of its origins. If the diamond was sourced from Zimbabwe, it is best not to deal with it, and ignorance of the law would not protect the trader, said Gardner.